Oral Surgery Coding & Reimbursement Alert

ICD-10 Update:

Split Cysts of Oral Soft Tissues Two Ways With K09.1 and K09.8

Hint: Use different codes for gingival cysts and cysts associated with tongue.

When your oral surgeon diagnoses a patient with any cysts of the soft tissues in the oral region such as dermoid or epidermoid cysts, you will have to report the cysts with a generalized ICD-10 code that includes all soft tissue cysts in that area.

Good news: This is similar to the way you would report this diagnosis with ICD-9 codes. However, there are some small changes to the type of cysts that are included under ICD-9 and ICD-10 codes.

ICD-9: When reporting cysts of the oral region, you report this diagnosis with the ICD-9 code, 528.4 (Cysts of oral soft tissues). You will use the same ICD-9 code to report a diagnosis of cysts of the oral soft tissues such as:

  • Dermoid cysts
  • Epidermoid cysts
  • Epstein's pearl of mouth
  • Lymphoepithelial cyst of mouth
  • Nasoalveolar cyst of mouth
  • Nasolabial cyst of mouth

Caveat: Although the descriptor to the ICD-9 code, 528.4 reads “cysts of the oral soft tissues,” you are not allowed to use this diagnosis code to report cysts of some oral soft tissues such as a gingival cyst or cyst involving the tongue. You report these with other ICD-9 codes. You report a gingival cyst with the ICD-9 code, 523.8 (Other specified periodontal diseases) and a cyst involving the tongue with 529.8 (Other specified conditions of the tongue).

ICD-10: As in ICD-9, you do not have specific diagnosis codes to describe each of the type of cysts that occur in the oral soft tissues. Again, you will have to rely on reporting a more generalized code that encompasses different types of oral soft tissue cysts. When you begin using ICD-10 codes, the ICD-9 code 528.4 that you use for a diagnosis of cysts of the oral soft tissues will crosswalk to K09.8 (Other cysts of oral region, not elsewhere classified).

ICD-10 change: You will use the ICD-10 code, K09.8, to report different cysts of the oral soft tissues. As in ICD- 9, this code should be used to report a diagnosis of cysts such as dermoid cysts, epidermoid cysts, Epstein’s pearl of mouth and Lymphoepithelial cyst of mouth. However, you cannot use this diagnosis code to report nasoalveolar cyst of the mouth and nasolabial cyst of the mouth. You have to report these two types of cysts with a different ICD-10 code. You will report these cysts with K09.1 (Developmental [nonodontogenic] cysts of oral region).

Example: Your oral surgeon reviews a 26-year-old male patient with complaints of a slow progressively developing mass in the area below the tongue. The patient said that the problem was there from the past two to three years and the mass was slowly enlarging in size, creating difficulties in chewing food and in swallowing. The patient did not complain of pain although he said that there was some degree of pain experienced from time to time.

Upon examination, your surgeon noticed a round mass in the sublingual area that seemed to displace the tongue superiorly and to some extent in the posterior direction. Your surgeon also notes that the mass is seen and palpated extraorally in the submental area.

Your surgeon ordered for a CT scan of the mass that revealed the presence of a well-circumscribed epidermoid cyst in the deep sublingual and the submental area.Your oral surgeon planned removal of the cyst through blunt dissection using an extraoral approach.

What to report: You report the removal of the epidermoid cyst using the CPT® code 41116 (Excision, lesion of floor of mouth). You report the diagnosis using 528.4 if you are reporting ICD-9 codes or use K09.8 if you are reporting with ICD-10 system of codes.